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		<title>three.js webgl - KTX2 texture loader</title>
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		<div id="info">
			<a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> - webgl - KTX2 texture loader<br />
			<a href="http://github.khronos.org/KTX-Specification/" target="_blank" rel="noopener">KTX2</a> with
			<a href="https://github.com/binomialLLC/basis_universal" target="_blank">Basis Universal GPU Texture Codec</a>
		</div>

		<!-- Import maps polyfill -->
		<!-- Remove this when import maps will be widely supported -->
		<script async src="https://unpkg.com/es-module-shims@1.3.6/dist/es-module-shims.js"></script>

		<script type="importmap">
			{
				"imports": {
					"three": "../build/three.module.js",
					"three/addons/": "./jsm/"
				}
			}
		</script>

		<script type="module">

			import * as THREE from 'three';

			import { KTX2Loader } from 'three/addons/loaders/KTX2Loader.js';
			import { OrbitControls } from 'three/addons/controls/OrbitControls.js';

			let camera, scene, renderer, controls;

			init().then( animate );

			async function init() {

				const width = window.innerWidth;
				const height = window.innerHeight;

				renderer = new THREE.WebGLRenderer( { antialias: true } );
				renderer.setSize( width, height );
				renderer.outputEncoding = THREE.sRGBEncoding;
				document.body.appendChild( renderer.domElement );

				window.addEventListener( 'resize', onWindowResize );

				scene = new THREE.Scene();
				scene.background = new THREE.Color( 0x202020 );

				camera = new THREE.PerspectiveCamera( 60, width / height, 0.1, 100 );
				camera.position.set( 2, 1.5, 1 );
				camera.lookAt( scene.position );
				scene.add( camera );

				controls = new OrbitControls( camera, renderer.domElement );
				controls.autoRotate = true;

				// PlaneGeometry UVs assume flipY=true, which compressed textures don't support.
				const geometry = flipY( new THREE.PlaneGeometry() );
				const material = new THREE.MeshBasicMaterial( {
					color: 0xFFFFFF,
					side: THREE.DoubleSide
				} );
				const mesh = new THREE.Mesh( geometry, material );
				scene.add( mesh );

				const formatStrings = {
					[ THREE.RGBAFormat ]: 'RGBA32',
					[ THREE.RGBA_BPTC_Format ]: 'RGBA_BPTC',
					[ THREE.RGBA_ASTC_4x4_Format ]: 'RGBA_ASTC_4x4',
					[ THREE.RGB_S3TC_DXT1_Format ]: 'RGB_S3TC_DXT1',
					[ THREE.RGBA_S3TC_DXT5_Format ]: 'RGBA_S3TC_DXT5',
					[ THREE.RGB_PVRTC_4BPPV1_Format ]: 'RGB_PVRTC_4BPPV1',
					[ THREE.RGBA_PVRTC_4BPPV1_Format ]: 'RGBA_PVRTC_4BPPV1',
					[ THREE.RGB_ETC1_Format ]: 'RGB_ETC1',
					[ THREE.RGB_ETC2_Format ]: 'RGB_ETC2',
					[ THREE.RGBA_ETC2_EAC_Format ]: 'RGB_ETC2_EAC',
				};

				// Samples: sample_etc1s.ktx2, sample_uastc.ktx2, sample_uastc_zstd.ktx2
				const loader = new KTX2Loader()
					.setTranscoderPath( 'jsm/libs/basis/' )
					.detectSupport( renderer );


				try {

					const texture = await loader.loadAsync( './textures/compressed/sample_uastc_zstd.ktx2' );

					console.info( `transcoded to ${formatStrings[ texture.format ]}` );

					material.map = texture;
					material.transparent = true;

					material.needsUpdate = true;

				} catch ( e ) {

					console.error( e );

				} finally {

					loader.dispose();

				}


			}

			function animate() {

				requestAnimationFrame( animate );

				controls.update();

				renderer.render( scene, camera );

			}

			function onWindowResize() {

				const width = window.innerWidth;
				const height = window.innerHeight;

				camera.aspect = width / height;
				camera.updateProjectionMatrix();
				renderer.setSize( width, height );

			}

			/** Correct UVs to be compatible with `flipY=false` textures. */
			function flipY( geometry ) {

				const uv = geometry.attributes.uv;

				for ( let i = 0; i < uv.count; i ++ ) {

					uv.setY( i, 1 - uv.getY( i ) );

				}

				return geometry;

			}

		</script>

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